/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.flink.table.planner.plan.nodes.exec.serde;

import org.apache.flink.annotation.Internal;
import org.apache.flink.configuration.Configuration;
import org.apache.flink.table.planner.plan.nodes.exec.ExecNodeBase;

/**
 * Custom filtering for {@link Configuration} used by {@link ExecNodeBase#getPersistedConfig()} to
 * avoid serializing null or empty configurations.
 */
@Internal
public class ConfigurationJsonSerializerFilter {

    @Override
    public boolean equals(Object obj) {
        if (obj == null) {
            return true;
        }
        if (obj instanceof Configuration) {
            Configuration other = (Configuration) obj;
            return other.toMap().isEmpty();
        }
        return true;
    }
}
